1. Field of the Invention
The present invention relates generally to internal axis single-rotation machines and more particularly, to machines, of the type comprising an internal rotor and an external rotor mounted for intermeshing rotation about their own centers of gravity at uniform angular velocities within a casing which surrounds the rotors.
2. Description of Related Art
In the existing literature, a book "Einteilung der Rotations-Kolbenmaschinen" (1963, Deutsche Verlags-Anstalt GmbH Stuttgart) or "Rotary Piston Machine" (London, Iliffe, 1965) by the Applicant of the present application shows numerous structural arrangements for internal axis rotary piston machines, wherein a special design which is a single-rotation machine is involved. The external rotor rotating about a fixed axis may itself control the inflow and outflow ports in the machine casing of this type of device so that internal compression is possible without requiring any additional means. A machine of this type is known, for example, in the prior art from DOS No. 2,456,252. In this type of device, a bead-like profiling of the internal rotor of the machine is kinematically produced by internal corner areas of the external area. Machines of this type will have dead spaces, due to the fact that when the profiling of the internal rotor moves into recesses of the external rotor, it will not displace the complete contents or volume of the recesses because the profiling will not extend to the outer periphery of the rotor. Thus, when the machine is constructed as a compressor, compressed gas will be fed back to the suction side of the machine. Any reduction in the size of such dead spaces will lead to mechanical weakening of the external rotor and the result is that it is not capable of being loaded at high rotational speeds.
Accordingly, the present invention is directed toward providing an improved machine of the type described, wherein, due to the shape of its rotors, there may be achieved a higher drive throughput relative to its structural volume, as well as a reduction of dead spaces, while permitting high rotational speeds for the rotors.